RILPL1 and Parkinson disease: The interaction of RILPL1 with phosphorylated Rab proteins interferes with ciliogenesis (6,13,14) and, in cholinergic neurons in the striatum, leads to disruption of a Sonic hedgehog neuroprotective circuit that supports dopaminergic neurons, providing a pathway by which LRRK2 may be linked to PD pathology (13).